Research Of Ka Band TE₀₁ Mode Circular Waveguide Bend

During the high microwave’s transmitting, waveguide bend is an extremelyimportant part which can make the wave energy high efficiently transmitted. Thus, itmakes significance sense for its research. This thesis gives a deep research about Kawave band TE01mode circle waveguide bend in different ways. Below are the generalcontents:1. It deduced the couple wave equation under the condition of axis of bending andradius of the gradient smooth wall circular waveguide and induced their couplingcoefficient。Introduced mode-matching technology in full range and elaboratelydeduced the mode-matching matrix equation of single step mutations and multistagestep mutations electromagnetic field.2. It made program of axis of bending circular waveguide bend according to couplewave theory, by comparing the results from CST calculating and Matlab valuecalculating to prove the validity of the latter, got the final result that TE01modetransmitting efficiency can be over98%when the center frequency is30.5GHz. andTE01mode constant curvature circular waveguide bend with over90%transmittingefficiency&over16%relative bands.3. According to the coupled strength relationship among circle waveguide modes,it adopted ellipse waveguide to avoid the coupling between TE01mode与TM11mode asmuch as possible to lower their coupling strength. Through CST andinterpolation function, it designed out the TE01mode variable curvature ellipticalwaveguide bend with transmitting efficiency at98.8%, over99%, over98%and over92%when center frequencies are at30.5GHz, from28.5GHz to30GHz, from30GHz to31.5GHz and relative bands at16.4%respectively.4. It designed out miter bend according to quasi-optical theory. It mainlyintroduced the procedure of making mode converter。 It started with the spreading ofGaussian mode and the selection of Gaussian beam waist and mouth radius. And thendesigned out the required mode switch through optimizing program of GeneticAlgorithm. Finally, it optimized the miter bend by HFSS and got the miter bend with transmitting efficiency over98%for center frequency at30.5GHz and workingefficiency over96%&relative bands over9.8%. It ended with project diagram drawingand processing.